kurlberg

9 ms·

31.
by kurlberg 6y ago
Low tech approach: Lehmer's bicycle chain sieve: https://en.wikipedia.org/wiki/Lehmer_sieve
32.
by kurlberg 6y ago
The resolution of this "paradox" is at the heart of "Quantum Chaos", the study of the relationship between classical chaos and quantum mechanics. In a chaotic system, minute differences in initial conditions are quickly
33.
by kurlberg 6y ago
Maybe not: that ZFS needs ECC is "common wisdom", but the disaster scenario appears not so likely. See https://news.ycombinator.com/item?id=14207520 https://news.ycombinator.com/item?id=8293025
34.
by kurlberg 6y ago
An amusing, surprising and in hindsight obvious lower bound for average random access speed in an array containing N "words" is N^(1/3) (cube root of N.) I.e., for any realizable computer without new physics.
35.
by kurlberg 6y ago
Awesome: Scott Manley has a youtube video about it (see https://www.youtube.com/watch?v=A8abMJhmvss. ) Heh, some of it did not age so well: 2012: work starts on Mars station. Elon, hurry up! :-)
36.
by kurlberg 6y ago
As a kid I loved reading "Great Space Battles" and "Spacecraft, 2000-2100 A.D.: Terran Trade Authority Handbook", by Stewart Cowley, from the late 70s. My impression is that the art (very beautiful airbrush(?) space shi
37.
by kurlberg 7y ago
Well, they also quote him as saying: "I’m suddenly concerned that all of published math is wrong because mathematicians are not checking the details, and I’ve seen them wrong before,”
38.
by kurlberg 7y ago
An ugly way around it is to compile your own version of unison. The good news, if I remember correctly, is that the binary can be built in one place and copied around to the other hosts (and say put in $HOME/bin.)
39.
by kurlberg 7y ago
My amiga c compiler (aztex manx) allowed either 16 or 32 bit ints. All/most systems libraries used 32 bit parameters, despite this I insisted on the 16 bit version "for performance". In hindsight this was sort of insane: one
40.
by kurlberg 7y ago
A long time ago, as part of a "Industry Study Visits"-course at university, we went to visit Asea-Atom and were told about the "PIUS" reactor ("Process Inherent Ultimate Safety"). Supposedly the construction w
41.
by kurlberg 8y ago
I don't know how far you have gotten, but I think it is a good idea to start with FFT-based fast multiplication and read up on whatever unknowns you encounter. In particular I think some abstract algebra (e.g. Dummit-Foote) would be he
42.
by kurlberg 8y ago
Throughout the years my employers have reinstalled servers and consequently changed host keys. I believe many users just accept the new key without realizing what they might get themselves into. Ideally your organization should keep updated
43.
by kurlberg 8y ago
Voevodsky developed Univalent Foundations in order to catch subtle mistakes in his (and others) result: "Only then did I discover that the proof of a key lemma in my paper contained a mistake and that the lemma, as stated, could not be
44.
by kurlberg 8y ago
Already Freakonomics noted/claimed that reading to kids makes little difference to educational outcome, whereas having lots books at home matters. The following explanation (taken from https://abcnews.go.com/WNT/s
45.
by kurlberg 8y ago
An interesting point made in https://web.math.princeton.edu/~kollar/FromMyHomePage/fm-ess... is that getting a fields medal is good for longevity, but bad if you "nearly got it": +8 yrs if you get it, -6
46.
by kurlberg 8y ago
You are compiling it with "make -j 8" (or -j 4), right?
47.
by kurlberg 9y ago
My 5c: both Fraleigh and Dummit & Foote are pretty good.
48.
by kurlberg 9y ago
I'm quite happy with a squeezebox server running on a linux computer, and music streamed to a Squeezebox Radio. Sadly these cannot be bought anymore, but there is a chromecast plugin that works with squeezebox server - I can then strea
49.
by kurlberg 9y ago
You can export from org to pdf (type C-c C-e l p in emacs). For some fine tuning you can export to tex and then use pdflatex.
50.
by kurlberg 9y ago
Check out latexmk: it keeps track of having to run bibtex etc, and runs latex "enough times" so that all equation refs etc have stabilised. (Latexmk -pdf to build a pdf, default is dvi.)
51.
by kurlberg 9y ago
Not quite a computation, but there is a striking example (due to Xia) where 5 particles interact and "kicks" off one particle to infinity in finite time. Further details can be found in http://www.ams.org/notice
52.
by kurlberg 9y ago
In an old discussion regarding ECC/ZFS (in particular, whether hitting bad RAM while scrubbing could corrupt more and more data), user XorNot kindly took a look the ZFS source and wrote "In fact I'm looking at the RAID-Z code
53.
by kurlberg 10y ago
Interestingly the idea of these trapdoor primes goes back to 1992 (by Gordon, see section 4 "Heidi hides her polynomials" of the paper above.)
54.
by kurlberg 10y ago
Favorite Stepanov quote below - apparently mixing mathematics and bad fish is quite potent: Question: What is the origin of STL? Has STL been conceived to be what it is now, that is "the" C++ Standard Library, or does it come from
55.
by kurlberg 10y ago
There is a quite nice web comic in which a Hermes 3000 typewriter plays a big role - The Guy I almost Was, see electricsheepcomix.com/almostguy/
56.
by kurlberg 10y ago
For emacs users I strongly recommend whizzytex + advi (at least if you find advi in your repos; it's somewhat painful to build advi on your own.) Almost as good is emacs + auctex - the first C-c C-c compiles the file, the second bring
57.
by kurlberg 10y ago
The devil is in the details: one possible outcome is that researchers must pay journals for open access publication, and this could change "'small science' fields" into 'big science' ones. I.e., a good but not
58.
by kurlberg 10y ago
One would hope that 35+ percent overhead would cover rent/heating etc.
59.
by kurlberg 10y ago
Brute force is not needed, check out "continued fraction" (in particular "11. Best rational approximations" at wikipedia.)
60.
by kurlberg 10y ago
On a whim I gave w3m (or w3m-el to be precise) a try on this page, and it worked - I found a new adblocker-blocker-blocker, and I'm quite happy I did got to read this gem of a summary at the end of the article: >In short, the mathem

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